package com.hmall.user.mapper;

import com.hmall.user.pojo.User;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;
@Mapper
public interface UserMapper extends BaseMapper<User> {
    //获取用户名字
    @Select("select username from tb_user where id =${id}")
    String getName(Integer id);
}